The bayesian classifier can only score new messages after it already learn 200 known spams and 200 known hams.
This article will guide you to configure related components to store SpamAssassin Bayes data in SQL server, and allow webmail users to report spam with one click.
Referencessection at the end of this article before asking questions.
We need to create a SQL database and necessary tables to store SpamAssassin bayes data. The RPM package installed on CentOS 6 doesn't ship SQL template for bayes database, so we have to download it from Apache web site. We're running SpamAssassin-3.3.1, so what we need is this SQL template file: http://svn.apache.org/repos/asf/spamassassin/tags/spamassassin_release_3_3_1/sql/bayes_mysql.sql If you're running different version, please find the proper SQL file here: http://svn.apache.org/repos/asf/spamassassin/tags/.
# cd /root/ # wget http://svn.apache.org/repos/asf/spamassassin/tags/spamassassin_release_3_3_1/sql/bayes_mysql.sql
Create MySQL database and import SQL template file:
# mysql -uroot -p mysql> CREATE DATABASE sa_bayes; mysql> USE sa_bayes; mysql> SOURCE /root/bayes_mysql.sql;
Create a new MySQL user (with password
sa_user_password) and grant
permissions. IMPORTANT NOTE: Please replace password
by your own password.
mysql> GRANT SELECT, INSERT, UPDATE, DELETE ON sa_bayes.* TO sa_user@localhost IDENTIFIED BY 'sa_user_password'; mysql> FLUSH PRIVILEGES;
/etc/mail/spamassassin/local.cf, add (or modify below settings):
use_bayes 1 bayes_auto_learn 1 bayes_auto_expire 1 # Store bayesian data in MySQL bayes_store_module Mail::SpamAssassin::BayesStore::MySQL bayes_sql_dsn DBI:mysql:sa_bayes:127.0.0.1:3306 # Store bayesian data in PostgreSQL #bayes_store_module Mail::SpamAssassin::BayesStore::PgSQL #bayes_sql_dsn DBI:Pg:sa_bayes:127.0.0.1:5432 bayes_sql_username sa_user bayes_sql_password sa_user_password # Override the username used for storing data in the database. # This could be used to group users together to share bayesian filter data. # You can also use this config option to trick sa-learn to learn data as a # specific user. # # In iRedMail, SpamAssassin is called by Amavisd, so we must set it to be # same as Amavisd daemon user: # - on Linux, it's user `amavis`. # - on FreeBSD, it's user `vscan`. # - on OpenBSD, it's user `_vscan`. bayes_sql_override_username amavis
Make sure SpamAssassin will load bayes modules:
# /etc/init.d/amavisd stop # amavisd -c /etc/amavisd/amavisd.conf debug 2>&1 | grep -i 'bayes' May 16 09:59:33 ... SpamAssassin loaded plugins: ..., Bayes, ... May 16 10:27:38 ... extra modules loaded after daemonizing/chrooting: Mail/SpamAssassin/BayesStore/MySQL.pm, Mail/SpamAssassin/BayesStore/SQL.pm, ...
Looks fine, now press
Ctrl-C to terminate above command, and start Amavisd
service again normally:
# /etc/init.d/amavisd restart
It is required to initialize the database by learning a message. We use the sample spam email shipped in the RPM package provided by CentOS 6:
# rpm -ql spamassassin | grep 'sample-spam' /usr/share/doc/spamassassin-3.3.1/sample-spam.txt # sa-learn --spam --username=amavis /usr/share/doc/spamassassin-3.3.1/sample-spam.txt Learned tokens from 1 message(s) (1 message(s) examined)
Run SQL commands below to check how many spams/hams have been learnt (note: the numbers will be different on your server):
mysql> USE sa_bayes; mysql> SELECT username,spam_count,ham_count FROM bayes_vars; +----------+------------+-----------+ | username | spam_count | ham_count | +----------+------------+-----------+ | amavis | 3 | 38 | +----------+------------+-----------+
Don't forget to update
backup_pgsql.sh if you're running PostgreSQL backend) to backup this newly
sa_bayes database. For example:
# Part of file `/var/vmail/backup/backup_mysql.sh` DATABASES='... sa_bayes'